Would you change a 315 CMH for quantum strips?

Hi

I was planning to run a 315 CMH and 200 vero watts to fill a 4 x 4 tent.

Prices are coming down on the strips and i can replace my 315 with 240 watts of strips. Does that make sense do you think?

I think I have to stop buying lights. But it is pretty nice for a bulb blow out to be impossible. Safety first and all.

I would run 240 watts of strips over half the tent and 200 watts of vero and the 135 quantum board if needed to cover the 4 x 4. I have way smaller tower fans and the reservoirs are out of the tent so it is all plant this time around.

315 and 200 is 32 watts a foot
240 and 200 is 27.5 watts a foot but i can add a 135 to get me to 36

315CMH all the way.

This looks like a diminishing return question. I'm not familiar with the cost or longevity of CMH elements but they offer close to the same efficacy as good leds. Based on my pair of 320w Vero arrays as well as another 240w of sammy strips in a 5x4 space, you're going to need more than 440w of leds to get a decent PPFD.

GBAUTO said:

but they offer close to the same efficacy as good leds.

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It's nowhere near.

GBAUTO said:

This looks like a diminishing return question. I'm not familiar with the cost or longevity of CMH elements but they offer close to the same efficacy as good leds. Based on my pair of 320w Vero arrays as well as another 240w of sammy strips in a 5x4 space, you're going to need more than 440w of leds to get a decent PPFD.

Click to expand...

CMH is 1.95 uMols/J efficient. Thats bare bulb efficiency. You lose at least 10% of that to reflector losses. Samsung strips are easily 2.5 uMol's/J, depending on how hard or soft you push them. So, no, they are not even close. They are not much more efficient than 600W HPS.

I hear what you say about efficiency but....a 315 can grow an LB in a 4 x 4. For a whopping 340 watts.

Bulbs last 20k hours which is not as much as a blurbple (50k) or a quantum or cob (100kish). but still pretty damned ok.

For me it is quality and what i can produce with 4 in a 4 x 4. But I think I am getting that damned fixture. I might get a 3 x 3 tent and just run 2 plants in each to make life easier

https://thegrowkit.ca/product/240w
Check out the strips. Maybe someone can tell me if they are decent and if i were to make them what it would cost roughly in Canada.

If they are selling for 300 maybe i can make one for 200

If you swap to led you may want to consider adding some uvb bulbs into the mix during flowering. That will be the main thing you lose if you get rid of the cmh.

Don't be shy g. Run all 3!

gwheels said:

https://thegrowkit.ca/product/240w
Check out the strips. Maybe someone can tell me if they are decent and if i were to make them what it would cost roughly in Canada.

If they are selling for 300 maybe i can make one for 200

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They look like a copy of the Samsung double row strips. No way to know what diode they are using. Price is decent, accounting for the exchange rate thats close to a dollar per watt. I sell them a bit less than that but I don't use the HLG drivers either.

You could probably make one for about that. 44$ CAD per strip and $73 for the driver, available on Digikey.ca. Probably find a sheet of aluminum scrap somewhere....

If I had room, I would not change CMH to LED, no way in hell. I do have about 500 watts of Quantum as veg lights though.